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Cyber Forensics
Table of Contents
Cyber Forensics—A Field Manual for Collecting, Examining, and Preserving Evidence of
Computer Crimes 1
Disclaimer 6
Introduction 7
Background 8
Dimensions of the Problem 9
Computer Forensics 10
Works Cited 11
Section I: Cyber Forensics 13
Chapter List 13
13
Chapter 1: The Goal of the Forensic Investigation 14
Overview 14
Why Investigate 14
Internet Exceeds Norm 14
Inappropriate E−mail 16
Non−Work−Related Usage of Company Resources 17
Theft of Information 18
Violation of Security Parameters 18
Intellectual Property Infraction 19
Electronic Tampering 20
Establishing a Basis or Justification to Investigate 21
Determine the Impact of Incident 22
Who to Call/Contact 24
If You Are the Auditor/Investigator 24
Resources 25
Authority 25
Obligations/Goals 25
Reporting Hierarchy 25

Escalation Procedures 25
Time Frame 26
Procedures 26
Precedence 26
Independence 26
Chapter 2: How to Begin a Non−Liturgical Forensic Examination 27
Overview 27
Isolation of Equipment 27
Cookies 29
Bookmarks 31
History Buffer 32
Cache 34
Temporary Internet Files 35
Tracking of Logon Duration and Times 35
Recent Documents List 36
Tracking of Illicit Software Installation and Use 37
i
Table of Contents
Chapter 2: How to Begin a Non−Liturgical Forensic Examination
The System Review 38
The Manual Review 41
Hidden Files 42
How to Correlate the Evidence 43
Works Cited 44
Chapter 3: The Liturgical Forensic Examination: Tracing Activity on a Windows−Based
Desktop 45
Gathering Evidence For Prosecution Purposes 45
Gathering Evidence Without Intent to Prosecute 45
The Microsoft Windows−Based Computer 46
General Guidelines To Follow 48

Cookies 50
Bookmarks/Favorites 53
Internet Explorer's History Buffer 54
Temporary Storage on the Hard Drive 55
Temporary Internet Files 56
System Registry 57
Enabling and Using Auditing via the Windows Operating System 61
Confiscation of Computer Equipment 65
Other Methods of Covert Monitoring 66
Chapter 4: Basics of Internet Abuse: What is Possible and Where to Look Under the
Hood 68
Terms 68
Types of Users 69
E−Mail Tracking 69
IP Address Construction 69
Browser Tattoos 69
How an Internet Search works 70
Swap Files 74
ISPs 75
Servers 75
Works Cited 75
Chapter 5: Tools of the Trade: Automated Tools Used to Secure a System Throughout
the Stages of a Forensic Investigation 77
Overview 77
Detection Tools 77
Protection Tools 84
Analysis Tools 87
Chapter 6: Network Intrusion Management and Profiling 91
Overview 91
Common Intrusion Scenarios 91

Intrusion Profiling 95
Creating the Profile 96
Conclusion 103
ii
Table of Contents
Chapter 7: Cyber Forensics and the Legal System 105
Overview 105
How the System Works 105
Issues of Evidence 106
Hacker, Cracker, or Saboteur 108
Best Practices 115
Notes 115
Acknowledgments 116
Section II: Federal and International Guidelines 117
Chapter List 117
117
References 118
Chapter 8: Searching and Seizing Computers and Obtaining Electronic Evidence 118
Recognizing and Meeting Title III Concerns in Computer Investigations 123
Computer Records and the Federal Rules of Evidence 131
Proposed Standards for the Exchange of Digital Evidence 134
Recovering and Examining Computer Forensic Evidence 140
International Principles for Computer Evidence 141
Chapter 9: Computer Crime Policy and Programs 143
The National Infrastructure Protection Center Advisory 01−003 143
The National Information Infrastructure Protection Act of 1996 146
Distributed Denial of Service Attacks 157
The Melissa Virus 163
Cybercrime Summit: A Law Enforcement/Information Technology Industry Dialogue 163
Chapter 10: International Aspects of Computer Crime 165

Council of Europe Convention on Cybercrime 165
Council of Europe Convention on Cybercrime Frequently Asked Questions 168
Internet as the Scene of Crime 168
Challenges Presented to Law Enforcement by High−Tech and Computer Criminals 169
Problems of Criminal Procedural Law Connected with Information Technology 169
Combating High−Tech and Computer−Related Crime 169
Vienna International Child Pornography Conference 171
OECD Guidelines for Cryptography Policy 171
Fighting Cybercrime: What are the Challenges Facing Europe? 171
Chapter 11: Privacy Issues in the High−Tech Context 172
Law Enforcement Concerns Related to Computerized Databases 172
Enforcing the Criminal Wiretap Statute 174
Referring Potential Privacy Violations to the Department of Justice for Investigation
and Prosecution 174
Testimony on Digital Privacy 175
Chapter 12: Critical Infrastructure Protection 176
Attorney General Janet Reno's Speech on Critical Infrastructure Protection 176
Protecting the Nation's Critical Infrastructures: Presidential Decision Directive 63 176
The Clinton Administration's Policy on Critical Infrastructure Protection: Presidential
iii
Table of Contents
Chapter 12: Critical Infrastructure Protection
Decision Directive 63 177
Foreign Ownership Interests in the American Communications Infrastructure 187
Carnivore and the Fourth Amendment 188
Chapter 13: Electronic Commerce: Legal Issues 195
Overview 195
Guide for Federal Agencies on Implementing Electronic Processes 195
Consumer Protection in the Global Electronic Marketplace 196
The Government Paperwork Elimination Act 196

Internet Gambling 197
Sale of Prescription Drugs Over the Internet 197
Guidance on Implementing the Electronic Signatures in Global And National
Commerce Act (E−SIGN) 198
Part I: General Overview of the E−SIGN Act 198
The Electronic Frontier: the Challenge of Unlawful Conduct Involving the Use of the
Internet 215
Internet Health Care Fraud 217
Jurisdiction in Law Suits 218
Electronic Case Filing at the Federal Courts 225
Notes 226
Chapter 14: Legal Considerations in Designing and Implementing Electronic
Processes: A Guide for Federal Agencies 229
Executive Summary 229
Introduction 237
I. Why Agencies Should Consider Legal Risks 238
II. Legal Issues to Consider in "Going Paperless" 242
III. Reducing The Legal Risks in "Going Paperless" 255
Conclusion 266
Notes 267
Chapter 15: Encryption 273
Department of Justice FAQ on Encryption Policy (April 24, 1998) 273
Interagency and State and Federal Law Enforcement Cooperation 273
Law Enforcement's Concerns Related to Encryption 273
Privacy in a Digital Age: Encryption and Mandatory Access 274
Modification of H.R. 695 280
Security and Freedom Through Encryption Act 281
OECD Guidelines for Cryptography Policy 285
Recommended Reading 285
Chapter 16: Intellectual Property 286

Prosecuting Intellectual Property Crimes Guidance 286
Deciding Whether to Prosecute an Intellectual Property Case 286
Government Reproduction of Copyrighted Materials 286
Federal Statutes Protecting Intellectual Property Rights 286
IP Sentencing Guidelines 289
Intellectual Property Policy and Programs 292
Copyrights, Trademarks and Trade Secrets 294
iv
Table of Contents
Section III: Forensics Tools 296
Chapter List 296
296
Chapter 17: Forensic and Security Assessment Tools 297
Detection, Protection, and Analysis 297
Detection and Prevention Tools for the PC Desktop 297
Analysis Tools 299
Applications 301
Additional Free Forensics Software Tools 307
Chapter 18: How to Report Internet−Related Crime 308
Overview 308
The Internet Fraud Complaint Center (IFCC) 309
Chapter 19: Internet Security: An Auditor's Basic Checklist 310
Firewalls 310
Supported Protocols 311
Anti−Virus Updates 311
Software Management Systems 312
Backup Processes and Procedures 312
Intra−Network Security 312
Section IV: Appendices 314
Appendix List 314

314
Appendix A: Glossary of Terms 314
A−C 314
D 317
E−G 319
H−I 322
K−Q 323
R−S 324
T−W 326
Appendix B: Recommended Reading List 329
Books 329
Articles 332
Web Sites 333
List of Exhibits 337
Chapter 2: How to Begin a Non−Liturgical Forensic Examination 337
Chapter 3: The Liturgical Forensic Examination: Tracing Activity on a Windows−Based
Desktop 337
Chapter 4: Basics of Internet Abuse: What is Possible and Where to Look Under the
Hood 337
Chapter 5: Tools of the Trade: Automated Tools Used to Secure a System Throughout
the Stages of a Forensic Investigation 338
Chapter 6: Network Intrusion Management and Profiling 338
Chapter 8: Searching and Seizing Computers and Obtaining Electronic Evidence 338
v
Table of Contents
List of Exhibits
Chapter 9: Computer Crime Policy and Programs 338
Chapter 11: Privacy Issues in the High−Tech Context 338
Chapter 12: Critical Infrastructure Protection 339
Chapter 13: Electronic Commerce: Legal Issues 339

Chapter 14: Legal Considerations in Designing and Implementing Electronic
Processes: A Guide for Federal Agencies 339
Chapter 18: How to Report Internet−Related Crime 339
vi
Cyber Forensics—A Field Manual for Collecting,
Examining, and Preserving Evidence of Computer
Crimes
ALBERT J. MARCELLA, Ph.D.
ROBERT S. GREENFIELD Editors
AUERBACH PUBLICATIONS A CRC Press Company
Boca Raton London New York Washington , D.C.
Library of Congress Cataloging−in−Publication Data
Cyber forensics: a field manual for collecting, examining, and preserving evidence of
computer crimes / Albert J. Marcella, Robert Greenfield, editors.
p. cm.
Includes bibliographical references and index.
ISBN 0−8493−0955−7 (alk. paper)
1. Computer crimes−−Investigation−−Handbooks, manuals, etc. I. Marcella, Albert J. II. Greenfield,
Robert, 1961−
HV8079.C65 C93 2001
363.25'968−−dc21
2001053817
This book contains information obtained from authentic and highly regarded sources. Reprinted
material is quoted with permission, and sources are indicated. A wide variety of references are
listed. Reasonable efforts have been made to publish reliable data and information, but the authors
and the publisher cannot assume responsibility for the validity of all materials or for the
consequences of their use.
Neither this book nor any part may be reproduced or transmitted in any form or by any means,
electronic or mechanical, including photocopying, microfilming, and recording, or by any information
storage or retrieval system, without prior permission in writing from the publisher.

All rights reserved. Authorization to photocopy items for internal or personal use, or the personal or
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1
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Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and
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Visit the Auerbach Publications Web site at www.auerbach−publications.com
Copyright © 2002 by CRC Press LLC
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International Standard Book Number 0−8493−0955−7
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Printed in the United States of America 1 2 3 4 5 6 7 8 9 0
Printed on acid−free paper
Editors and Contributors
Albert J. Marcella, Jr., Ph.D., CFSA, COAP, CQA, CSP, CDP, CISA, is an associate professor of
Management in the School of Business and Technology, Department of Management, at Webster
University, in Saint Louis, Missouri. Dr. Marcella remains the president of Business Automation
Consultants, an information technology and management−consulting firm he founded in 1984. Dr.
Marcella has completed diverse technical security consulting engagements involving disaster
recovery planning, site and systems security, IT, financial and operational audits for an international
clientele. He has contributed numerous articles to audit−related publications and has authored and

co−authored 18 audit−related texts.
Robert S. Greenfield, MCP, has over 16 years of experience as a programmer/analyst, with the
past five years as a systems consultant and software engineer in the consulting field. He has
extensive experience designing software in the client/server environment. In addition to mainframe
experience on several platforms, his background includes systems analysis, design, and
development in client/server GUI and traditional environments. His client/server expertise includes
Visual Basic, Access, SQL Server, Sybase, and Oracle 7.3 development. Mr. Greenfield has
created intranet Web sites with FrontPage and distributing applications via the Internet. He currently
holds professional accreditation as a Microsoft Certified Professional and continues self paced
training to achieve MCSE, MCSD, and MCSE/D + Internet ratings.
Abigail Abraham is an Assistant State's Attorney, prosecuting high−technology crimes for the Cook
County State's Attorney's Office in Chicago, Illinois. She was awarded her J.D. from The University
of Chicago Law School and served as an editor on the law review. Following law school, she
clerked for one year for the Honorable Danny J. Boggs, U.S. Court of Appeals for the Sixth Circuit.
She is an adjunct law professor at The University of Chicago Law School. In addition, she has
designed training for lawyers and for police officers, and lectures around the country on
2
high−technology legal issues.
Brent Deterdeing graduated from the University of Missouri with a degree in computer science and
a minor in economics. Brent's involvement with SANS is extensive. He is an author of an upcoming
book on firewalls through SANS, as well as chairing the SANS/GIAC Firewalls Advisory Board. He
has mentored both small and large classes through SANS/GIAC Security Essentials Training &
Certification (GSEC). Brent also authors, revises, and edits SANS courseware, quizzes, and tests.
He has earned the SANS/GIAC GSEC (Security Essentials), GCFW (Firewall Analyst — HONORS),
GCIA (Intrusion Analyst), and GCIH (Incident Handling) certifications, as well as being a Red Hat
Certified Engineer (RHCE). Brent participates in the St. Louis InfraGard chapter.
John W. Rado is a geospatial analyst at National Imagery and Mapping Agency (NIMA) in St.
Louis, Missouri. John has worked for NIMA since January of 1991.
William J. Sampias has been involved in the auditing profession for the past decade, with primary
emphasis on audits of information systems. Mr. Sampias has published several works in the areas

of disaster contingency planning, end−user computing, fraud, effective communications, and
security awareness. Mr. Sampias is currently director of a state agency information systems audit
group.
Steven Schlarman, CISSP, is a security consultant with PricewaterhouseCoopers. Since joining
the firm in 1998, Steve has covered a number of roles, mainly as the lead developer of the
Enterprise Security Architecture System and Services. He has published articles on the subject as
well as being one of the major thought leaders in the PricewaterhouseCoopers' Enterprise Security
Architecture Service line. Prior to joining the firm, Steve had worked on multiple platforms including
PC applications, networking, and midrange and mainframe systems. His background includes
system security, system maintenance, and application development. Steve has completed
numerous technical security consulting engagements involving security architectures, penetration
studies ("hacking studies"), network and operating system diagnostic reviews, and computer crime
investigation. He has participated in both PC computer forensic analysis and network intrusion
management and investigation. Prior to PricewaterhouseCoopers, Steve worked at a U.S. state law
enforcement agency in the information systems division.
Carol Stucki is working as a technical producer for PurchasePro.com, a rapidly growing dot.com
company that is an application service provider specializing in Internet−based procurement. Carol's
past experiences include working with GTE, Perot Systems, and Arthur Andersen as a programmer,
system analyst, project manager, and auditor.
Dedication
Erienne, Kristina, and Andy
Michael Jordan said it best, thus, what more can I say…
I approached practices the same way I approached games. You can't turn it on and
off like a faucet. I couldn't dog it during practice and then, when I needed that extra
push late in the game, expect it to be there. But that's how a lot of people fail. They
sound like they're committed to being the best they can be. They say all the right
things, make all the proper appearances. But when it comes right down to it, they're
looking for reasons instead of answers. If you're trying to achieve, there will be
roadblocks. I've had them; everybody has had them. But obstacles don't have to stop
you. If you run into a wall, don't turn around and give up. Figure out how to climb it,

3
go through it, or work around it.
You are each important, special and unique for so many reasons. Always remain close, protect,
respect, and love each other. Always know that I love each of you with all my heart.
Thank you Diane, for your constant support and love. My life is a far better one with you in my
world. Today, tomorrow, forever…
Al
This book is dedicated to my mother and father who always believed in me, gave me love,
guidance, and support in all of my pursuits. A son could not hope for better parents. Thank you both
and know that your love gives me strength every day.
To my wife for her patience, and love through it all. And a special thank you goes out to my
daughter Hannah, for your understanding, patience, love, wit, and unwavering support.
You are all the best and I love you.
I also would like to recognize Dr. Marcella for giving me this opportunity. Thank you.
Bob
Acknowledgments
As senior editor for this text, the responsibility to acknowledge and thank all the individuals who
have contributed their expertise, time, energies, and efforts to the successful development of this
text falls to me. This is no easy task. It is difficult to put into words the appreciation and gratitude I
have for each of their efforts and to express appropriately to each of them my sincere thanks for
giving their time and themselves to make this text a better product. Simply mentioning each by
name here seems a bit inadequate in comparison to their individual and collective contributions.
Given the continual shifting technological landscape in which we all live and work, attempting to
harness even for a moment in time, this very technology, and to "look under the hood" so−to−speak,
was a daunting assignment. Those professionals whose insights and comments on the critically
important field of cyber forensics are included in this text, and deserve substantial credit and our
thanks for taking up this challenge and for their spot−on examination and evaluation of key cyber
forensics issues.
I wish to formally recognize each contributing author here, although briefly, and have included a
more extensive personal profile for each author. To each of you, please know that you have my

heartfelt gratitude and personal thanks for your willingness to contribute your talents and expertise
to this text.
Thank You:
To my co−editor Bob Greenfield; thank you for contributing your talents in the technical systems
arena and for your piece on "The Liturgical Forensic Examination: Tracing Activity on a
Windows−Based Desktop."
Thanks to Steve Schlarman, security consultant at PricewaterhouseCoopers, who wrote the chapter
on "Network Intrusion Management and Profiling," and to Brent Deterdeing, network security
4
manager, enabling technologies at Solutia, Inc., for insights and comments on "Tools of the Trade:
Automated Tools Used to Secure a System Throughout the Stages of a Forensic Investigation."
John Rado, geospatial analyst at National Imagery and Mapping Agency; thank you for sharing your
thoughts (and your extensive security/forensics background and library with me), and for developing
the focused piece on "Basics of Internet Abuse: What is Possible and Where to Look Under the
Hood."
From the Financial and Computer Crime Department of the State Attorney's office of Cook County,
Illinois, Attorney Abigail Abraham; thank you for your engaging examination into "Cyber Forensics
and the Legal System."
To my long−time colleagues and collaborators Carol Stucki, for your presentations on the "The Goal
of the Forensic Investigation" and "How to Begin a Nonliturgical Forensic Examination;" and Bill
Sampias for your efforts in developing the areas of guidelines and tools, including the list of critical
recommended readings.
Additionally, I would like to thank Carol for all the work she did in compiling the exhaustive reference
materials from the Federal Bureau of Investigation, computer examinations library, which appeared
in successive issues of the Bureau's Handbook of Forensic Services.
Without the contributions of these talented professionals, this text would have been a lesser
product.
Last, but by far certainly not the least, I want to acknowledge and thank Christian Kirkpatrick,
Acquisitions Editor at Auerbach Publications, for her constant confidence that this text would
emerge from a simple concept into a viable product.

Christian, thank you for your steadfast support throughout the lengthy development process that
has led to the creation of this viable cyber forensics field manual.
5
Disclaimer
As always with texts of this nature, here is the disclaimer….
The information contained within this field manual is intended to be used as a reference, and not as
an endorsement of the included providers, vendors, and informational resources. Reference herein
to any specific commercial product, process, or service by trade name, trademark, service mark,
manufacturer, or otherwise does not constitute or imply endorsement, recommendation, or favoring
by the authors or the publisher.
As such, users of this information are advised and encouraged to confirm specific claims for product
performance as necessary and appropriate.
The legal/financial materials and information that are available for reference through this manual are
not intended as a substitute for legal/financial advice and representation obtained through
legal/financial counsel. It is advisable to seek the advice and representation of legal/financial
counsel as may be appropriate for any matters to which the legal/financial materials and information
may pertain.
Web sites included in this manual are intended to provide current and accurate information; neither
the authors, publisher, nor any of its employees, agencies, and officers can warranty the information
contained on the sites and shall not be held liable for any losses caused on the reliance of
information provided. Relying on information contained on these sites is done at one's own risk. Use
of such information is voluntary, and reliance on it should only be undertaken after an independent
review of its accuracy, completeness, efficacy, and timeliness.
Throughout this manual, reference links to other Internet addresses have been included. Such
external Internet addresses contain information created, published, maintained, or otherwise posted
by institutions or organizations independent of the authors and the publisher. The authors and the
publisher do not endorse, approve, certify, or control these external Internet addresses and do not
guarantee the accuracy, completeness, efficacy, timeliness, or correct sequencing of information
located at such addresses. Use of such information is voluntary, and reliance on it should only be
undertaken after an independent review of its accuracy, completeness, efficacy, and timeliness.

6
Introduction
As an auditor as well as researcher and author, I realize and value the importance of timely,
well−focused, accurate information. It is with this philosophy in mind that the development of this
project was undertaken.
To the reader, a note of explanation…. This is not a text, but rather a field manual. It has been
written — better yet, compiled — and edited in a manner that will allow you to rapidly access a
specific area of interest or concern and not be forced to sequentially wade through an entire text,
chapter by chapter, to get to what is important to you.
In the true sense of a field manual, each "chapter" (and we use that term loosely) stands on its own
and presents focused, timely information on a specific topic related to cyber forensics. The author of
each "chapter" was selected for his or her expertise in a specific area within the very broad field of
cyber forensics.
Often a limiting aspect of most projects, especially those written on emerging technical topics, is the
inability to cover every aspect of the topic in a single all−inclusive text. This truth befalls this field
manual that you are about to use.
Initial research into this growing discipline proved that it would be next to impossible to include all
the areas of both interest and importance in the field of cyber forensics that would be needed and
required by all potential readers and users in a single text. Thus, this field manual presents specific
and selected topics in the discipline of cyber forensics, and addresses critical issues facing the
reader who is engaged in or who soon will be (and you will!) engaged in the preservation,
identification, extraction, and documentation of computer evidence.
As a user of this field manual, you will see that this manual's strength lies with the inclusion of an
exhaustive set of chapters covering a broad variety of forensic subjects. Each chapter was
thoroughly investigated; examined for accuracy, completeness, and appropriateness to the study of
cyber forensics; reviewed by peers; and then compiled in a comprehensive, concise format to
present critical topics of interest to professionals working in the growing field of cyber forensics.
We finally had to select several key areas and put pen to paper, entice several colleagues to share
their ideas, and resign ourselves to the fact that we cannot say all that needs to be said in one text,
book, or manual. We trust the material we have included will serve as a starting point for the many

professionals who are beginning their journey into this exciting discipline.
We begin our journey into the realm of this relatively new discipline by opening with a brief
discussion as to the current state of the environment relating to the need for this new field of
forensics and then a brief examination of the origins of cyber forensics. Along the way, we will
establish several basic definitions designed to assist the reader in moving easily through what could
be difficult and confusing terrain.
Although e−mail is becoming more mission−critical for enterprises, it also has the
ability to haunt a company in times of trouble, because records of e−mail messages
remain in the company systems after deletion — a feature highlighted during the
Microsoft anti−trust trial. The case has featured critical testimony derived from old
Microsoft e−mail messages.
—InfoWorld, 10/25/99
7
Background
The ubiquitous use of computers and other electronic devices is creating a rapidly rising wave of
new and stored digital information. The massive proliferation of data creates ever−expanding digital
information risks for organizations and individuals. Electronic information is easy to create,
inexpensive to store, and virtually effortless to replicate. As a result, increasingly vast quantities of
digital information reside on mass storage devices located within and without corporate information
systems. Information risks associated with this data are many. For example, electronic data can
often show — with a high degree of reliability — who said, knew, took, shared, had and did what,
and who else might be involved in the saying, knowing, taking, sharing, having, and doing. For the
corporation, the free flow of digital information means that the backdoor is potentially always open to
loss.
To put the explosive growth of electronic data in perspective, consider that Americans were
expected to send and receive approximately 6.8 trillion e−mail messages in 2000 — or about 2.2
billion messages per day.
[1]
Although some of this e−mail is sent and received by individuals, most
of it is being created by and sent from corporate mail servers.

In 2000, the World Wide Web consisted of 21 terabytes of static HTML pages and is growing at a
rate of 100 percent per year.
[2]
There are now about 2.5 billion indexed Web pages, increasing at
the rate of 7.3 million pages per day.
Demand for digital storage is expected to grow by more than 1800 percent between 1998 and 2003.
A midrange estimate of the amount of data currently stored on magnetic tape is 2.5 exabytes (an
exabyte is 1 million terabytes), with another 2.5 exabytes stored on computer hard drives.
[3]
Contrasting the growth of paper pages and electronic documents adds additional perspective. The
growth of recorded information doubles every three to four years. Over 93 percent of all information
produced in 1999 was in digital format. About 80 percent of corporate information currently exists in
digital form. Companies are expected to generate some 17.5 trillion electronic documents by 2005,
up from approximately 135 billion in 1995.
[4]
Some 550 billion documents now exist online.
There is more to this explosive growth than just "documents." Additional forms of electronic data
originate from:
Internet−based electronic commerce, online banking, and stock trading•
Corporate use and storage of phone mail messages and electronic logs•
Personal organizers, such as the Palm Pilot (worldwide PDA sales were expected to total
about 6 million units in 2000 rising to 17 million in 2004.)
•
Wireless devices such as cell phones and pagers with contacts and task list storage
(worldwide mobile phone sales were expected to total about 400 million in 2000, rising to
560 million in 2004
[5]
)
•
Digital cameras•

Corporate use and storage of graphic images, audio, and video•
These are several of the factors now at work in corporations that increase the risk of litigation and
loss of confidential corporate data (from www.fiosinc.com/digital_risk.html, Fios, Inc. (877)
700−3467, 921 S.W. Washington Street, Suite 850, Portland, Oregon 97205)
It is best to state up−front that the emphasis in any cyber forensic examination must be on the
forensic element, and it is vital to understand that forensic computing, cyber forensics, or computer
forensics is not solely about computers. It is about rules of evidence, legal processes, the integrity
8
and continuity of evidence, the clear and concise reporting of factual information to a court of law,
and the provision of expert opinion concerning the provenance of that evidence:
Companies are very concerned about the notion that anything they write
electronically can be used again at any time. If you have to discipline yourself to
think, "can this be misconstrued?" that greatly hampers your ability to communicate
and introduces a huge level of inefficiency.
—David Ferris, president of Ferris Research (San Francisco)
[1]
University of California at Berkeley, School of Information Management and Systems, October
2000, />[2]
University of California at Berkeley, School of Information Management and Systems, October
2000, />[3]
University of California at Berkeley, School of Information Management and Systems, October
2000, />[4]
Designing a Document Strategy: Documents…Technology…People. Craine, K., MC2 Books,
2000.
[5]
University of California at Berkeley, School of Information Management and Systems, October
2000, />Dimensions of the Problem
Crime: an act committed in violation of the law.
Much of today's computer−related crime is not a violation of formal law. In 1979, the Justice
Department defined computer crime as any illegal act for which knowledge of computer technology

is essential for its perpetration, investigation, or prosecution.
Criminal law is a crime, which is a wrong against society, typically leading to a conviction, which
normally results in jail term or probation. The main purpose is punishment of the offender. Most
computer crimes in United States today go unpunished (which weakens deterrence of law).
Evidence must be gathered by law enforcement in accordance with court guidelines governing
search and seizure (Fourth Amendment):
The right of the people to be secure in their persons, houses, papers, and effects,
against unreasonable searches and seizures, shall not be violated, and no warrants
shall issue, but on probable cause, supported by oath or affirmation, and particularly
describing the place to be searched, and the persons or things to be seized.
Computer crime is escalating!
The FBI's caseload is increasing dramatically. In FY 1998, the FBI opened 547 computer intrusion
cases; in FY 1999, that jumped to 1154. At the same time, because of opening the National
Infrastructure Protection Center (NIPC) in February 1998 and the FBI's improving ability to fight
cyber crime, the Bureau closed more cases. In FY 1998, the closed case file increased to 399
intrusion cases; and in FY 1999 it increased to 912 such cases.
However, given the exponential increase in the number of cases opened, cited above, the FBI's
actual number of pending cases has increased by 39 percent, from 601 at the end of FY 1998 to
834 at the end of FY 1999. In short, although the FBI has markedly improved its capabilities to fight
cyber intrusions, the problem is growing even faster.
9
The Computer Security Institute released its fifth annual "Computer Crime and Security Survey" for
2001, confirming the alarming facts cited above. Eighty−five percent of respondents detected
security breaches over the past 12 months.
At least 64 percent of respondents reported financial losses, including theft of proprietary
information, financial fraud, system penetration by outsiders, data or network sabotage, and
denial−of−service attacks. Information theft and financial fraud caused the most severe financial
losses, put at $151 million and $93 million, respectively. The losses from 186 respondents totaled
just over $377 million.
Losses traced to denial−of−service attacks were only $77,000 in 1998, and by 1999 had risen to

just $116,250. Further, the new survey reports on numbers taken before the high−profile February
2000 attacks against Yahoo!, Amazon, and eBay. Finally, many companies are experiencing
multiple attacks; 19 percent of respondents reported ten or more incidents.
Attorney Deanne Siemer says she tells judges that digital technology "takes
one−third out of the trial time." And that's a huge factor for courts with their enormous
backlogs.
— Rebecca Ganzel,
"Digital Technology in the Courtroom,"
Presentations, November 1999
Computer Forensics
Computer Forensics deals with the preservation, identification, extraction, and documentation of
computer evidence. The field is relatively new to the private sector but it has been the mainstay of
technology−related investigations and intelligence gathering in law enforcement and military
agencies since the mid−1980s.
Like any other forensic science, computer forensics involves the use of sophisticated technology
tools and procedures that must be followed to guarantee the accuracy of the preservation of
evidence and the accuracy of results concerning computer evidence processing.
What evidence is needed?
All physical evidence (computer, peripherals, notepads, documentation, etc.)•
Visual output on the monitor•
Printed evidence on a printer•
Printed evidence on a plotter•
Film recorder (magnetic representations)•
It is extremely important to realize that evidence must have been gathered in accordance with the
Fourth Amendment and the Electronic Communications Privacy Act (ECPA), and that
computer−generated evidence is considered "hearsay" with some exclusions. Depending on your
role or responsibility in the computer forensics investigation, you may be subject to differing sets of
rules and regulations. Internal investigators, for example, are not subject to the Fourth Amendment
stipulations; however, they are subject to the ECPA.
Typically, computer forensic tools exist in the form of computer software. Computer forensic

specialists guarantee accuracy of evidence processing results through the use of time−tested
10
evidence processing procedures and through the use of multiple software tools, developed by
separate and independent developers. The use of different tools that have been developed
independently to validate results is important to avoid inaccuracies introduced by potential software
design flaws and software bugs.
The introduction of the personal computer in 1981 and the resulting popularity came with a mixed
blessing. Society in general benefited, but so did criminals using personal computers in the
commission of crimes. Today, personal computers are used in every facet of society to create and
share messages, compute financial results, transfer funds, purchase stocks, make airline
reservations, and access bank accounts and a wealth of worldwide information on essentially any
topic.
Computer forensics is used to identify evidence when personal computers are used in the
commission of crimes or in the abuse of company policies. Computer forensic tools and procedures
are also used to identify computer security weaknesses and the leakage of sensitive computer data.
In the past, documentary evidence was typically stored on paper and copies were made with carbon
paper or photocopy machines.
Most documents are now stored on computer hard disk drives, floppy diskettes, Zip disks, and other
forms of removable computer storage media. Computer forensics deals with finding, extracting, and
documenting this form of "electronic" documentary evidence (www.forensics−intl.com/def4.html).
Along the way, prior to formally pursuing a cyber forensics investigation, several important and
critical questions must be asked:
What is the policy in the organization to report and deal with computer crime? (It may be
nonexistent, or it may be not well thought out or tested, or it may even be incompetent.)
•
Do you "really" want to prosecute?•
Who do you call in law enforcement and what will be their reaction?•
Additional questions that should be considered and appropriate answers well thought out include:
Can you afford to be without the evidence?•
Are you willing to see this go public?•

Was a thorough investigation conducted?•
Did you violate the ECPA or any privacy issues?•
How will you prove the crime?•
Is there any likelihood of the suspect doing damage prior to arrest? (Dr. Rayford Vaughn,
<>)
•
Obtaining concrete answers to these questions prior to embarking on a cyber forensics audit or
investigation is critical. Doing so may help shield the organization (as well as the
investigator/auditor/security personnel, etc.) from civil or criminal liabilities.
The material presented in the following pages of this field manual has been selected, developed,
and shared with the specific objective of providing the reader with a resource with which to become
better prepared to undertake and participate in the cyber forensics audit of a suspect system.
Works Cited
1. University of California at Berkeley, School of Information Management and Systems, October
2000, />11
2. Designing a Document Strategy: Documents…Technology…People. Craine, K., MC2 Books,
2000.
12
Section I: Cyber Forensics
Chapter List
Chapter 1: The Goal of the Forensic Investigation
Chapter 2: How to Begin a Non−Liturgical Forensic Examination
Chapter 3: The Liturgical Forensic Examination: Tracing Activity on a Windows−Based Desktop
Chapter 4: Basics of Internet Abuse: What is Possible and Where to Look Under the Hood
Chapter 5: Tools of the Trade: Automated Tools Used to Secure a System Throughout the Stages
of a Forensic Investigation
Chapter 6: Network Intrusion Management and Profiling
Chapter 7: Cyber Forensics and the Legal System
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Chapter 1: The Goal of the Forensic Investigation

Overview
Carol Stucki
Any investigation has a purpose. With this chapter we will start with the reasons why one would
need to conduct an investigation involving computers. When we understand the reason why we are
conducting the investigation, then we can develop a plan of action on how to conduct that
investigation, and where to look for evidence. The information gathered during the investigation can
be used for the enforcement of Human Resources (HR) rules for disciplinary action and even legal
action. Therefore, the reasons for the investigation are almost as important as the investigation
itself.
This chapter reviews several reasons why an investigation is needed and the plan of that
investigation, based on those reasons. It also reviews the impact of the action that resulted in the
complaint. We first need to determine the impact or feasibility of conducting the investigation. For
example, if the cost of the investigation outweighs the benefits, there might not be a reason to
conduct the investigation. For the most part, the decision to conduct the investigation is up to
management. However, it is the investigators' responsibility to provide the information on which to
allow management to base the decision to proceed.
The deliverables from this chapter will be either a recommendation to proceed with the investigation
and a plan of action to do so, or to withdraw due to a lack of evidence or justification. With the plan
in hand, you will be able to take the steps outlined in the following chapters to implement the
investigation. You will actually conduct the investigation and use the tools as described to gather the
information and evidence needed to reach a conclusion in your investigation.
Why Investigate
First we will need to consider the complaint or the initial reason for conducting an investigation.
Some typical reasons that may warrant an investigation include but are not limited to:
Internet usage exceeds norm•
Using e−mail inappropriately•
Use of Internet, e−mail, or PC in a non−work−related manner•
Theft of information•
Violation of security policies or procedures•
Intellectual property infractions•

Electronic tampering•
This chapter reviews the typical reasons for investigation and lists some questions to help
determine what facts or circumstances surround each reason.
Internet Exceeds Norm
If the complaint is that someone's Internet usage is too high, we should first determine the basis for
this complaint. It should also be determined whether the above normal Internet usage was identified
14
through electronic monitoring or by personal observation. It is also appropriate to determine if the
usage is out−of−line with company standards for the type of job responsibilities held by the
individual under investigation. Equally important is to determine how those standards were
determined and developed.
There are different questions to be asked, and answered, in order to investigate the claim,
depending on the basis of the complaint.
If the usage was electronically monitored:
Did a firewall monitor the usage?1.
Was the usage monitored by Internet Protocol (IP) address or individual identification (ID)?2.
What exactly was monitored? (e.g., time, sites, keywords, etc.)3.
Can more than one person use this personal computer (PC) (or IP address)?4.
Can more than one person use this ID?5.
Can the usage times/dates be correlated to physical access by the individual under
investigation? (If monitoring shows access was between 8 a.m. and 10 a.m., was the
individual at work during this time?)
6.
What was the pattern of access?7.
How does this compare with the individual's work schedule?8.
Could the individual have logged in and then not logged out? (i.e., get to an Internet site and
then go to another task on the PC, thus leaving the Internet site up and running?)
9.
Are there timeouts set on the Internet access? On the PC login?10.
Are there security cameras, login sheets, key card access logs, or timecards that can verify

that it was the individual who accessed the Internet via this PC?
11.
Is there a pattern to the usage?12.
Once you obtain answers to these questions you will begin to see the outlines of a plan of the
investigation forming. For example, if Joe Programmer is accused of exceeding Internet norms,
based on a report generated from the firewall monitoring system, we can ask some additional
questions to validate the concern/ complaint.
If the pattern of unusually high utilization was after−hours when Joe was not scheduled to be at
work, then there might be a deeper issue that will require further investigating to uncover (i.e., who
and how someone was using Joe's ID after−hours). However, if the case is simply that Joe is
logging into the Internet first thing in the morning to check the latest news or stock quotes, and not
logging out, this is a case where the monitoring or rules might need to be adjusted to account for the
high usage. Alternatively, Joe may simply need a refresher course on the company's Internet usage
policies.
On the other hand, if the usage concern was based on a person's observation of Joe's actions,
there is another, slightly different set of questions to ask, such as:
Who made the observation?1.
Are logs available to support the observation? (e.g., login, logout, timecards, firewall access,
etc.)
2.
Are there other witnesses to support the observation?3.
What exactly was the individual under investigation observed doing?4.
What is the pattern of usage?5.
Are there security cameras, login sheets, time cards, or key card access logs that can verify
the individual under investigation had access and was logged on to the Internet?
6.
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Again, once you obtain answers to these questions you will begin to formalize a plan of
investigation. This plan will differ slightly from the plan based on electronic monitoring. With
observation being the basis for a complaint, the ability to verify the usage is more difficult to

substantiate — but not impossible.
There are a variety of tools, methods, and techniques outlined in this text that will allow you to
substantiate the claim, if there is any evidence. For example, there are several files located on the
firewall and the PC that can be retrieved, displayed, and reviewed in order to prove or disprove the
above−normal access violation(s).
The above−normal utilization should prompt the investigator and management to inquire about the
impact (financial, physical, operational, etc.) of the so−called excessive usage. Several questions to
help evaluate the impact include:
What damage (if any) did the excessive usage cause?1.
How can the damage be substantiated?2.
How can the damage be quantified?3.
Did the individual under investigation not meet his or her job responsibilities as a result of
excessive Internet usage?
4.
Did the individual under investigation interfere with another person's job performance as a
result of the excessive utilization?
5.
Was someone offended by the usage (e.g., inappropriate materials, games being played)?6.
Can you identify this person?7.
Is the person willing to state for the record that he or she she was offended by the usage?8.
Did fraud occur in the form of falsified timesheets — hours of work reported, or any other
form, as a result?
9.
The answers to these questions answers will not only help form the plan for this type of
investigation, but will also help the investigator and management determine if the investigation
should be (can be) pursued.
Inappropriate E−mail
Before performing any investigation on e−mail, you need to ensure that corporate policy allows it.
New electronic privacy laws protect the privacy of electronic communications. If corporate policy
specifically states that all computers and data stored on them belong to the corporation, then you

are probably on safe ground. Be sure that there is such a policy and that the employee under
investigation has read the policy before proceeding. Although this is one of the easiest
investigations, this type of investigation should be done strictly by the book. If the corporate policy
does not contain the rights to the employee's e−mail, then you and your corporation could be
subject to a lawsuit for invading the privacy of an employee.
If the reason for an investigation is that there was inappropriate use of e−mail, either through the act
of sending offensive material or for personal and non−work−related use, there is yet another set of
questions that should be asked. These questions will help determine if there was inappropriate
utilization of the company's e−mail systems and if further investigative action is required.
What was sent?1.
Can you obtain a copy from the complainant or recipient?2.
Is a copy available from the automated e−mail archive system?3.
Was someone offended? (This could be an harassment issue and require HR involvement.)4.
16
Who if anyone else received the material?5.
Was the individual under investigation the originator of the e−mail, or was it someone else?6.
How were you able to (or can you) validate this?7.
Could someone else have sent the e−mail, using the ID of the individual under investigation?8.
Are screen−saver passwords used?9.
Could someone else use the PC of the individual under investigation?10.
Was the time that the e−mail was sent during the time the individual under investigation had
access to e−mail?
11.
Is auto−forwarding of e−mail used? Available? Activated?12.
Was a group list used?13.
Are there patterns or history to the e−mail usage?14.
Have there been previous warnings to the individual under investigation about the e−mail
usage?
15.
If so, are these warnings documented?16.

What was the intent of the e−mail?17.
Some of the questions listed in the section on abnormal Internet utilization can also be applied to
this type of investigation. The real issue with this type of investigation is to determine whether it is
an issue of harassment or a case of violating company e−mail policies/procedures.
Potential exposures to the company, which can result from the lack of a proactive response by
management to a harassment complaint, include a lawsuit filed against the company by the
complainant, as well as multiple instances of harassment that can lead to multiple lawsuits.
Furthermore, to make matters worse, the longer the company waits to investigate, the more likely it
is that lawyers will have a field day and turn this into the company not caring, and thus higher
rewards to the complainant. To alleviate the appearance of a non−proactive response to
harassment complaints, the company should have anti−harassment policies and training programs.
This training should be repeated annually for all employees. There should be documentation that is
maintained in HR files stating that each employee has attended and signed a statement that he or
she has read the company's policies against harassment. This is also documentation that should be
gathered during the investigation.
Non−Work−Related Usage of Company Resources
If the reason for the investigation is about non−work−related use of company resources (i.e., PC,
e−mail, or access to the Internet), the above questions apply, but there are additional questions that
should be asked, including:
What exactly occurred? (Was the individual under investigation using his or her PC to
engage in "moonlighting" work, e−mail for personal use, etc.?)
1.
When did the incident occur?2.
How was it documented?3.
How often or how much does this happen?4.
Is the individual under investigation the only person engaged in this activity, or are there
others?
5.
How can you determine this?6.
Is the action a widely accepted company practice, albeit a violation of company policy?7.

Did the individual under investigation take the action for personal financial gain?8.
Was the non−work−related usage for personal use?9.
Is there a liability to the company due to the unauthorized use of company property?10.
17
These more detailed questions will help frame the direction of the investigation more clearly. Thus,
a more appropriate plan of action can be devised and carried out. The main issue with this type of
investigation concerns the inappropriate use of company property for personal gain, and whether
the inappropriate usage violated any standing company policies.
Theft of Information
The theft of information raises the intensity and seriousness of an investigation to levels that may
exceed those established in previously discussed scenarios. The intensity of an investigation into
the theft of information will vary, depending on what type of information was stolen, its significance
to the company's ability to remain competitive, the nature and sensitivity of the information stolen,
and what was done with the stolen information.
Some of the previously mentioned questions can be applied to this type of investigation. However,
there are additional questions that relate specifically to the theft of information, including:
What type of information was stolen?1.
How has this been (or can this be) verified?2.
How much information was stolen?3.
How was the information stolen?4.
What is the impact or cost of the loss?5.
How can this loss be quantified?6.
How can this be substantiated?7.
Is the cost of the loss tangible or intangible (competitive information can be intangible)?8.
Has the goodwill of the company been damaged as a result of the theft?9.
Has the company lost a competitive edge due to the theft?10.
Was the information totally lost (e.g., copied and then erased or destroyed), or was it
copied?
11.
Was another company's information, beyond your own, compromised?12.

What was the level of security surrounding the information lost?13.
Who had access to the stolen information?14.
Can this be verified?15.
Are access logs available?16.
Are they free from potential, external tampering?17.
Were there procedures in place for the safe handling/accessing of the lost information?18.
Was the information proprietary, confidential, or restricted?19.
How was this classification determined and communicated?20.
To determine exactly how the information was stolen, you might need to perform further security
and access audits/reviews. For the purpose of planning and investigation, the investigator should
develop a sense of how the information was stolen. One reason to quickly determine how the
information may have been stolen is an attempt to prevent further information from being stolen in
the same manner.
Violation of Security Parameters
Violation of security parameters can vary widely, from an individual simply failing to properly log off
when leaving work to covert hacking into secured files. Security parameters are not always those
dramatic measures of using guards, secret codes, retinal scanners, and IDs, but they do include the
18